Problem: Solve for $t$ : $-16 = -3 + t$
Solution: Add $3$ to both sides: $ \begin{eqnarray} \\ \hphantom{-16 {+ 3}} &\hphantom{=}& \hphantom{t} \\ -16 &=& -3 + t \\ \\ {+3} && {+3} \\ \end{eqnarray} $ $ \begin{eqnarray} \\ -16 {+ 3} &=& t \\ \end{eqnarray} $ Simplify. $ t = -13$